Improvement in wrenches



Patented Sept. 1,1874.

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NITED STATES PATENT OFFICE.

BENJAMIN F. JOSLYN, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO RICHARD P. BRUFF, OF NEWYORK CITY.

IMPROVEMENT IN g WRENCHSES.

Specification forming part of Letters Patent No. 154,680, dated September 1, 1874; application filed January 2, 1784.

To all whom it may concern:

Beit known that I, BENJAMIN F. JosLYN, of Worcester, county of Worcester, State of Massachusetts, have invented certain Improvements in Wrenches, of which the following is a specication:

The main object of my invention is the adjustment of the movable jaw of a wrench, either by a rapid or by a slow and exact movement, and this object I attain by so combining a worm, a', with the jaw A, and with a rack, a, on the stem B of the wrench, as shown in Figures 1 and 2 of the accompanying drawings, that the said Worm can be thrown outof gear with the rack when it is desirable to move the jaw rapidly from or toward the perthe rack when'a slowvlnovement and nice ad' j ustinent of the jaw, by turning the worm, is required.

The jaw A is made hollow, and of the form best observed in the sectional plan, Fig. 3, on line l 2, Fig. 1, and is arranged to slide on the stem B of thewrench in the usual manner. Within the jaw is contained the spindle D, on one end of which is formed the above-mentioned worm or screw the opposite end projecting through the open rear of the jaw, and having a collar, p, for bearing against-the end of the same. The spindle has a groove, f, to whichisadaptedafulcrum-pin,6,driventhrough the jaw, and a spring, h, within the latter tends to maintain the spindle in the position shown in Fig. l, with its Worm in gear with the rack. When it is desirable to quickly move the jaw A from'or toward the permanent jaw m, all that is necessary is for the voperator to place his thumb on the serrated knob t at the end of the spindle, and press it toward the stem B of the wrench, thereby throwing the worm out of gear with the rack, as shown in Fig. 2, and permitting the jaw to be moved in any direction desired. When a delicate adjustment of the jaw is required the spindle should be permitted to assume the position shown in Fig. l, where the worm is in gear with the rack,and the spindle, which has its bearings in the rear of the jaw, can be turned by manipulating its serrated knob.

It will be observed that as the rounded end of the spindle bears against the inside of the jaw, and that as the thread of the worm or screw w is beveled on one side and abrupt ou the other, the teeth of the rack being of corresponding shape, the strain to which the jaw is subjected must be transmitted ,through the worm directly to the abrupt sides of the teeth of the rack, and hence, that there can be no tendency of this strain to throw the worm out of gear. l

When it is desirable to confine anyobject securely between the jaws of the wrench, the movable jaw may rst be adjusted against the object, and then the spindle may be turned by means of a screw-driver applied to the slot n in the serrated .knob i, or the latter may be otherwise formed to receive a wrench or other instrument by which the necessary power may be applied to turn the spindle, ,with sufficient eii'ect to conne the object between the jaws.

The deterioration of screw wrenches is attributable more to their reckless use as hammers than to any other source,for the j arscaused by bringing the permanent jaw min violent contact with rigid objects have a destructive effect on the wrench. In order to obviate this evil I bore in that part of the permanent jaw which is generally used as the head ot' a hammer a recess for the reception of a block, y, of softer material than that of the jaw. j The block, for instance, may bemade of hard wood, brass, copper, or white metal, materials sufliciently hard to strike against any object which it is proper to strike with a screw-wrench, and soft enough to prevent any deteriorating jars.

I claim as my inventionj The combination of the stem B of the wrench, and its teeth a, with the worm-spindle D, retained in place by the fulcrum-pin e, and having a knob, i, projecting from the jaw, the Working parts being inclosed within the movable jaw, all as set forth.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing Witnesses.

' BENJAMIN F. JOSLYN.

Witnesses J. HENRY HILL, DAvin F. PARMENTER. 

